FOSSTL CARNIVORA 41 
skull) had larger brain capacity, and the modern forms still larger 
and better-developed brains. This indicates that slow but steady 
FIG. 16. SKULL OF THE PRIMITIVE MUSTELINE BUNAELURUS 
Oligocene of Colorado, ‘Three-halves natural size. Viewed from the under side to show the teeth 
increase in intelligence which has occurred in almost all the lines 
of evolution among quadrupeds. Superiority of brain ts the 
final test by which, in the long run, the persistence of a race ts decided. 
FIG. 17. SKULL OF MUSTELA OGYGIA 
An extinct species of marten, from the Middle Miocene of Colorado. Side view, natural size 
FELIDA, OR CATs. 
(Sabre-Tooth Tigers) 
Types: the mounted skeletons of Smilodon and Hoplophoneus, 
skeleton of Dinictis in block, skulls of Hoplophoneus, Dinictis, Arche- 
lurus. 
